Journal Article

Temperature effects on wood anatomy, wood density, photosynthesis and biomass partitioning of <i>Eucalyptus grandis</i> seedlings

D. S. Thomas, K. D. Montagu and J. P. Conroy

in Tree Physiology

Volume 27, issue 2, pages 251-260
Published in print February 2007 | ISSN: 0829-318X
Published online February 2007 | e-ISSN: 1758-4469 | DOI: http://dx.doi.org/10.1093/treephys/27.2.251
Temperature effects on wood anatomy, wood density, photosynthesis and biomass partitioning of Eucalyptus grandis seedlings

More Like This

Show all results sharing this subject:

  • Plant Sciences and Forestry

GO

Show Summary Details

Preview

Wood density, a gross measure of wood mass relative to wood volume, is important in our understanding of stem volume growth, carbon sequestration and leaf water supply. Disproportionate changes in the ratio of wood mass to volume may occur at the level of the whole stem or the individual cell. In general, there is a positive relationship between temperature and wood density of eucalypts, although this relationship has broken down in recent years with wood density decreasing as global temperatures have risen. To determine the anatomical causes of the effects of temperature on wood density, Eucalyptus grandis W. Hill ex Maiden seedlings were grown in controlled-environment cabinets at constant temperatures from 10 to 35 °C. The 20% increase in wood density of E. grandis seedlings grown at the higher temperatures was variously related to a 40% reduction in lumen area of xylem vessels, a 10% reduction in the lumen area of fiber cells and a 10% increase in fiber cell wall thickness. The changes in cell wall characteristics could be considered analogous to changes in carbon supply. Lumen area of fiber cells declined because of reduced fiber cell expansion and increased fiber cell wall thickening. Fiber cell wall thickness was positively related to canopy CO2 assimilation rate (Ac), which increased 26-fold because of a 24-fold increase in leaf area and a doubling in leaf CO2 assimilation rate from minima at 10 and 35 °C to maxima at 25 and 30 °C. Increased Ac increased seedling volume, biomass and wood density; but increased wood density was also related to a shift in partitioning of seedling biomass from roots to stems as temperature increased.

Keywords: biomass partitioning; CO2 assimilation; fiber cell; photosynthesis; xylem vessel

Journal Article.  0 words. 

Subjects: Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.